Abstract: The manufacture of an electrochemical sensor precursor comprising the steps of: preparing an electrically conductive biocomposite comprising an aqueous mixture of: polycationic conductive polymer particles; an anionic polyelectrolyte; or pre-existing composites of polycationic conducting polymers and anionic polyelectrolytes a biological affinity agent; and an optional buffer; applying the mixture to a region of an electroconductive surface; and removing water to allow adhesion of the biocomposite to the region of the surface.

Abstract: A protein stabilizer additive comprises two or more of a tris compound of the formula (1): (HOCH.sub.2).sub.3 --C--R, wherein R is: C.sub.1 -C.sub.4 alkyl, substituted C.sub.1 -C.sub.4 alkyl, NH.sub.2 ; NR.sup.1 R.sup.2 wherein R.sup.1 and R.sup.2 may be independently: H, C.sub.1 -C.sub.4 alkyl sulphonate, C.sub.1 -C.sub.4 hydroxyalkyl sulphonate; C.sub.1 -C.sub.4 alkyl NHC(CH.sub.2 OH).sub.3, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 hydroxyalkyl; C.sub.1 -C.sub.4 alkyl carboxylate; a polyelectrolyte; a buffer; and one or more additional components for example divalent metal salts.

Abstract: Provided is an odour sensor which may be useful for discriminating between the odour of human or other mammalian individuals, and perimidine monomers and polymers which may be used in such a sensor.